基于正则表达式的分割字符串

I have the output of a command in tabular form. I'm parsing this output from a result file and storing it in a string. Each element in one row is separated by one or more whitespace characters, thus I'm using regular expressions to match 1 or more spaces and split it. However, a space is being inserted between every element:

我有表格形式的命令的输出。我正在解析结果文件中的输出并将其存储在一个字符串中。一行中的每个元素由一个或多个空白字符分隔，因此我使用正则表达式匹配1个或多个空格，并将其拆分。但是，在每个元素之间插入了一个空格:

>>> str1="a    b     c      d" # spaces are irregular
>>> str1
'a    b     c      d'
>>> str2=re.split("( )+", str1)
>>> str2
['a', ' ', 'b', ' ', 'c', ' ', 'd'] # 1 space element between!!!

Is there a better way to do this?

有更好的方法吗?

After each split str2 is appended to a list.

在每个分割后的str2被追加到一个列表中。

4 个解决方案

#1

106

By using (,), you are capturing the group, if you simply remove them you will not have this problem.

通过使用(，)，您正在捕获组，如果您简单地删除它们，您就不会有这个问题。

>>> str1 = "a    b     c      d"
>>> re.split(" +", str1)
['a', 'b', 'c', 'd']

However there is no need for regex, str.split without any delimiter specified will split this by whitespace for you. This would be the best way in this case.

但是，不需要regex、string .split而不指定任何分隔符，将为您将其按空格分隔。在这种情况下，这是最好的办法。

>>> str1.split()
['a', 'b', 'c', 'd']

If you really wanted regex you can use this ('\s' represents whitespace and it's clearer):

如果你真的想要regex，你可以使用这个('\s'代表空格，它更清晰):

>>> re.split("\s+", str1)
['a', 'b', 'c', 'd']

or you can find all non-whitespace characters

或者您可以找到所有非空白字符。

>>> re.findall(r'\S+',str1)
['a', 'b', 'c', 'd']

#2

The str.split method will automatically remove all white space between items:

split方法将自动删除项目之间的所有空白:

>>> str1 = "a    b     c      d"
>>> str1.split()
['a', 'b', 'c', 'd']

Docs are here: http://docs.python.org/library/stdtypes.html#str.split

文档在这里:http://docs.python.org/library/stdtypes.html # str.split

#3

When you use re.split and the split pattern contains capturing groups, the groups are retained in the output. If you don't want this, use a non-capturing group instead.

当您使用re.split和split模式包含捕获组时，组将保留在输出中。如果你不想这样，可以使用非捕获组。

#4

Its very simple actually. Try this:

它其实非常简单。试试这个:

str1="a    b     c      d"
splitStr1 = str1.split()
print splitStr1

#1

106